This invention relates to aqueous coatings, particularly aqueous road-marking paint that dries quickly after application and is pH alkaline.
Various attempts to produce an aqueous road-marking paint as a substitute for solvent-based road marking paints have been disclosed in the art. A significant problem has been that the aqueous paints do not dry quickly enough.
European Patent Application No. 200249 discloses applying an aqueous dispersion of polymer to the road and then contacting the composition with a water soluble salt to cause the coating to dry rapidly and resist washout by a rain shower five minutes after application. This disclosure would require spraying with two compositions which would require the use of extra equipment.
European Patent application 0 066 108 discloses an aqueous road marking composition in which the binder is a mixture of a pure acrylic resin, a carboxylated styrene/dibutyl fumarate copolymer and a polymeric, polyfunctional amine such as polypropylenimine. This application states that the disclosed compositions are not storage stable beyond 48 hours after which more polyfunctional amine must be added to restore activity.